Rocker ring



NOV. 7, 1933- P BQLL|NGER ET AL 1,934,521

ROCKER RING Filed July 30, 1931 W/ 77V'55'5 I INVENTORS.

30/ Bo/lf/Jger and A Harr FHarf/Ylah ATTORNEY Patented Nov. 7, 1933 warren STATES PATENT OFFICE man, Pittsburgh, Pa.,

. assignors to Westinghouse Electric and Manufacturing Company, a corporation of Pennsylvania Application July 30, 1931. Serial No. 554,122

3 Claims.

Our invention relates to rocker rings for supporting the brushes of dynamo-electric machines and particularly to rocker rings for rail- Way motors.

5 In building a high-power motor for installa tion in limited space, such as is provided in a railway locomotive, it is often necessary to place various portions of the motor and the drive mechanism in such close proximity to each other that it is difficult to make proper inspection or replacement of the various parts. This has been particularly true of the brush rigging, the structure necessarily being such that it is inconvenient to properly inspect such parts.

To facilitate such inspections, it has been pro-- posed to mount the brush supports on an annular movable brush-holding ring, commonly called a rocker ring.

In practice, a window is furnished through 20 which a portion of the rocker ring may be inspected, and means are provided for shifting the ring to bring various portions in range for inspection.

As the ring members are most conveniently made of metal and the members for holding the brushes must necessarily be firmly attached to the ring members, it has been customary to provide the necessary insulation between the brush boxes and the members attached to the rocker rings. This has materially increased the space necessary for the brush box and its support so that the distance between adjacent brush-rigging parts has been materially decreased, so much so that it has been frequently found necessary to increase the commutator size in order to provide the necessary clearance between adjacent brush-rigging parts.

The rocker-ring assembly of our invention is so constructed as to eliminate the insulation between the brush support and the brush boxes and so materially reduce the overall dimensions of the brush rigging, thus securing adequate clearance between adjacent brush-rigging parts without increase in commutator size or, in some cases, with actual reduction of commutator size.

According to our invention, the brush boxes are directly attached to the brush-supporting members which are, in turn, rigidly attached to the rocker rings by moulded insulators having the necessary mechanical strength for supporting the brush rigging.

Other objects and advantages of our invention will be apparent from the following detailed description, taken in conjunction with the accompanying drawing, in which,

The figure is a sectional elevation of a portion of a railway motor embodying our invention.

The motor shown in the drawing comprises a rotor member 1 having a winding 2 connected to the commutator 5, of any desired size, and a stator member 6 inclosed in a frame 8 to which is attached end bells l0. Enclosed within this framework, is our rocker-ring assembly for maintaining the brushes in proper contact with the commutator.

Our improved rocker-ring assembly comprises, ring members 14 and 15 slidably mounted in suitable bearing surfaces 18 in the frame 8 of the motor. These ring members are spaced apart by suitable brush supporting or body members comprising a central body portion 20 adapted to directly support the brush boxes 21 which may be secured thereto in any suitable manner.

The central body portion of the brush supported members are provided with attaching members which consist of end members 25 adapted to be secured to the rings 14 or 15 by any suitable means, such as the bolts 26, the central body portion and the end portions being rigidly attached together by suitable molded insulators having the necessary mechanical strength.

For this purpose we have found a vitreous composition containing mica and known in the trade as Micalex to be most suitable.

This vitreous composition has adequate mechanical strength as well as the necessary insulating properties. It is also desirable in that the vitreous material will adhere firmly to both portions of the spacer member so that an intimate bond is maintained which will not readily work loose under the severe jarring it receives in use. This vitreous material has a further advantage in that it is easily moulded in a plastic state to any desired shape. Preferably the insulator 30 extends over a portion'of one of the members in order to provide an adequate creepage distance between the central body portion and the ring members.

Suitable current carrying leads 32 are assembled on the rocker ring assembly and supplied with current in any desired mamier (not shown). Suitable feeders (not shown) extend from the leads to the individual brushes.

Oneo'f the ring members is preferably provided 7 with a rack 35 meshing with a pinion 36 mounted in the end bell 10 so that the rocker ring may be moved to permit inspection of any of the individual brush supports or brushes.

While we have shown and described a specific embodiment of our invention, it is apparent that modifications and changes can be made therein without departing from the spirit and scope of our invention. We desire, therefore, that only such limitations shall be imposed as are suggested in the accompanying claims or as may be necessitated by the prior art.

We claim as our invention:

1. A rocker ring comprising a plurality of supporting rings, a plurality of spacer membersbetween said rings said spacer members comprising end members adapted to be secured to said rings, an intermediate member, molded insulators securing said intermediate member to said ends and a brush supporting member carried by said intermediate member.

2. A rocker ring comprising a plurality of supporting rings, a plurality of spacer members between said rings said spacer members comprising end members secured to said rings, an intermediate member secured to said end member by molded insulators, a brush supporting member carried by each of said intermediate members and means on one of said rings for rotating the rocker ring.

3. A rocker ring assembly comprising a plurality of annular ring members, a plurality of spacing members between said rings having ends for connection with said rings, members secured to said rings for connection with said ends and molded insulators for rigidly connecting said ends to said members.

PAUL BOLLINGER.

HARRY F. HARTMAN. 

